Artificial silk



Patented Oct. 25, 1932' UNITED STATES PATENT OFFICE HARE SCHUHMANN, OI BERLIN-CHARLOTTENBURG, AND FRIEDRICH STREUBER, OF

BERLIN-TEGEL, GERMANY, ASSIGNORS TO GENERAL ELECTRIC COMPANY, A COR- PORATION OF NEW YORK ARTIFICIAL SILK No Drawing. Application filed December 7, 1928, Serial No. 324,574, and in Germany January 11, 1928.

The present invention relates to the manufacture of artificial silk.

We have discovered that synthetic resins of the polyhydric alcohol-polybasic acid type, also known as alkyd resins, have the combination of properties required for textile fibres, and also that such resins may be fashioned, as by extrusion under high ressure, into the form of fine fibres. Such bres are highly elastic, strong and resistant to the action of chemical reagents and solvents.

In carrying out our invention a s nthetic resin is extruded through a fine ori ce at a temperature of about 150 to 200 C. The resin preferably should be carried to the intermediate stage of condensation commonly known as B-stage, but should not be carried to the final completely condensed C-stage, and may be associated with various plasticizing or softening agents, such as triphenyl or tricresyl phosphate, in accordance with known practice. Although our invention contemplates the use of an alkyd resin consisting mainly of g1 cerol and phthalic anhydride, other polyhy ric alcohols and other olybasic acids may be used in combination, or example, succmic acid ma be used to wholly or partly replace phtha ic anhydride, and glycols ma be used to replace the glycerine, either w olly or in art.

The resin from w ich the fibres are fashioned may be initially colored with suitable dyes thereby dispensin with a separate dyeing operation. The e filament resulting from the extrusion process is brought to a stage of final condensation by baking in order to impart to the filament the greatest elasticity and resistance to chemical reagents and solutions.

In accordance with a modification of our invention an alkyd resin (with or without plasticizing agents) may be s un from a solu-v tion into a coagulating bat in accordance with known ractice in the artificial silk manufacture. vsith this end in view the alkyd resin, while still in the A-stage is dissolved in solvents as for exam le in a mixture of acetone and alcohol an is extruded in filamentary forminto a water bath or other coagulatso ing agent, which may be at roomtemperature.

On leaving the coagulating agent the extrud ed material is dried and converted by baking to its C-stage, in which the resin is insoluble and non-fusible.

What we claim as new and desire to secure by Letters Patent of the United Stat-es is:

1. An artificial silk consisting of a condensation product of polyhydric alcohol and polybasic acid.

2. A textile fibre consisting of a condensation product of glycerine and phthalic anhydride.

3. A textile fibre consisting of an alkyd resin in an insoluble, non-fusible condition.

4. A textile fibre consistin of a plasticized condensation product of po yhydric alcohol and polybasic acid.

In witness whereof, we have hereunto set our hands this 17th day of November, 1928.

' HANS SCHUHMANN.

FRIEDRICH STREUBER. 

